Adjustable yarn tension device



April 29, 1941. R. H. CARTER ETAL ADJUSTABLE YARN TENSION DEVICE 2 SheetQfSheet l Filed July 29, 1939 (jme/m5 PAUJH Cfr@ TER Pfc/mko Gouw/6 @v C/mow/ck 5 //NG sal/RY April 29, 1941. R H. CARTER Erm.

ADJUSTABLE YARN TENSION DEVICE Filed July 29, 1939 2 Sheets-Sheet 2 llilll Patented Apr. 29,1941

ADJUSTABLE YARN TENSION DEVICE Ralph H. Carter and Richard Gollong, Johnson City, und Chadwick B. Killblll'y, Elizabethton, Tenn.,

assignors to North American Rayon Corporation, New York, N. Y., a' corporaf tion of Delaware Application July 29, 1939, Serial No. 287,288

11 Claims.

This invention relates to an adjustable yarn tensioning device and more particularly to a mechanism for use in conjunction with a spinning or twisting device ofthe kind adapted to impart two twists to the yarn, thread or the like for each revolution of the spindle.

The specic improvement contemplated by this invention is the provision of a simple rugged mechanism for insuring that the yarn will be subjected to a predetermined uniform tension during the twisting operation in order to control the rate of speed with which the yarn is drawn from the bobbin and thus eliminate irregular twisting of and defects in the yarn and produce a finished yarn of uniform twisting properties.

'I'he device herewith disclosed may be used with apparatus in which the yarn package from which the thread is drawn does not partake in the revolution ,ofy the twisting device. In such devices, the thread is drawn off from aI stationary package and led downwardly through a hollow rotating spindle, then outwardly around the yarn package where it formsy a balloon owing to the high rotational speed of the spindle, and nally to a. takeup device. 'I'he size of the balloon formed by the thread during twisting depends upon the rotational speed of the spindle `and particularly upon the rate of speed with which the yarn is drawn from the package. is obvious that a balloon formed by a heavy thread will draw the thread from the source of supply at a much faster rate of speed than a comparatively light thread, which is due to the high centrifugal force set up in the thread during ballooning. In the articial silk industry, for example, where threads ranging from about 50 to 600, 800 or more denier are produced, the high denier thread will draw the thread much faster from the yarn package than a comparatively light thread of, for, example, 50 denier, owing to the much greater centrifugal force during ballooning of the high denier thread. If, however, an adjustable braking means is inserted in the path of the thread from the spooi to the ballooning area, the pull of the balloon on the thread drawn from the package may be' regulated.

It is therefore one object ofthe present invention to provide a cap for twisting spools wherein the thread to be twisted is fed from the stationary yarn package in a downward axial direction of the package through a hollow rotating spindle, while subjecting the "yarn to the influence of an adjustable brake or tension mechanism which will insure, that the yarn will receive a precise tensioning action.

Another object is to construct such an adjust able yarn tensioning mechanism that may be readily assembled and disassembled and which e will give the operator precise control over the amount of tension imparted to the yarn.

A further object is to construct the brakingl arms of the device so that they may be easily released from contact with the yarn for adjust.- ment and the like and to fabricate the braking or tensioning members per se of a material which will not be scored or indented by the yarn passing therebetween.

Another still further object is 'to provide means for releasing the tensioning members and thus permit easy threading of the spindle and the iady removal of broken thread, slubs and the In the drawings,

Fig. 1 is a vertical sectional view showing the Vyarn package on the spindle and the balloon formed by the twisted yarn;

Fig. 2 is a side plan view of the twisting cap per se;

Fig. 3 is a bottom plan view of' the twisting cap; i

Fig. 4 is a separating key;

Fig. 5 is an enlarged vertical cross sectional view of the twisting head and tension device; FiFigg. 6- is atop plan view taken on line 6 9 vof Fig. 7 is an enlarged detail partly in cross section of a. modied form of tension arm;

Fig. 8 is a bottom plan view taken on line 8-8 of Fig. 9; and

Fig. 9 is a vertical section of the twisting head partly in cross section.

The package of yarn i to be twisted is carried on a spool or bobbin 2 tted on base 3` ailxed to disc 4 which is mounted on cup 5. The conventional rotating mechanism indicated'collectively by numeral 6 is arranged to turn .the hollow spindle I0 and it will lbe understood that this mechanism may be of any desired type as is well known in the art. l A

The hollow rotating spindle l0 has a vertical bore Il and side,opening i2 therein for the passage o! the thread, as will be hereinafter described. A stationary tube-like member I3 surrounds the operative tip I4 encompassing the upper end of the spindle lil-and extends upwardly to forma support for the twisting cap and adjustable tension device broadly designated I5. Y

Specifically, the cap I5 comprises an annular l support fitted over the end of tube I3 and surrounding the yarn centeringferrule 2I. 'I'he enlarged diameter portion of the cap is screwed or otherwise secured to the base plate 24 of the cone shaped casing 26 which terminates in twisting head 21 having a ring-like shoulder 23 and central tapered bore 29. The cone casing 26 is hollow and has a pair of opposite cut-away sections 30 and 3l.

A pair of spaced pivot blocks and 35 are ingages an arcuate socket formed on the underf sides of head 21 at the cut-away sections 30 and 3l, see Fig. 3.

The angled bracket arms 38 and 40 have mounted on their meeting faces friction pads or brakes and 5I, retained in sheet 'metal pivoted arms 39' and 40' and associated mechanism are similar to the preferred form, the difference being the construction of the head 21. Here, instead of having a key 80 and opening 32 for separating the brake arms, the spring catches B2 are retained within interrupted arcuate grooves 10. Oppositely positioned screws 1I and 1I pass through the upper part of the cone and terminate within interrupted slots 12-12. Thus, when the head 21 is rotated through a 90 angle, it positions the upper ends of the arms 33l and 40' opposite interrupted portions of the head having no arcuate ridge or grooves and the arms will pivot outwardly through sections 30 and 3i'.

In operation, the yarn from the package I, as shown in dotted lines, is led from the spool or bobbin 2 downwardly through cap opening 29 between opposed tension pads 50-5I, guide 2|, hollow rotating spindle II and outwardly from the bottom opening I2, and thence balloons around the --mechanism to a suitable collection device. During its path from the point of unwinding from the yarn package to the point of holders 52 and 53, respectively, which clamp the friction members and extend rearwardly to embrace the back of the arms 39 and 40 (see Fig. 6), the vertical position of the pad being maintained by horizontal stop pins 54. It is preferable to have at least one of the holders 52 and'53 adjustable with relation toy its arm and opposite pad and to this end thehoider arms are extended rearwardly so as not to bind against the back of its arm 39. To create a constant pressure on the friction pad 5I, a spring pressed plunger 55 encased in a screw threaded tube 55' is threaded through the bracket arm 39 with a screw threaded cap 56 bearing on the rear end of coil spring 51. Consequently when the cap 56 istumed, the pressure exerted by the pad 5I against the opposite pad may be adjusted.

As before described, the upper ends of the bracket arms and pads are normally in contact arcuate grooves 46. 'I'his is also assisted by springs 58 and 59 encircling the pivots 31 and 38, respectively.

When it is desired to separate the pads 50 and 5I for replacement, adjustment, rethreading and the like, a key SII' having a blade 5I is inserted through a bore 82 formed at right angles to the bracket arms 39 and 40. 'I'he blade 8| is placed between the arms below the pads and given a quarter turn which is sufllcient to snap the spring pressed pins 45 out of engagement with their locking grooves 45. After rethreading or adjustment has been made, the bracket arms may be readily locked into engagement again by applying pressure to the arms through openings 30 and 3|.

In Fig. '7 there illustrated a modified form of the armv and friction pad holder wherein the pivoted arm 39' has a pad 5I and holder 53 with constant tension devices 42' and 55'. These devices comprise hollow sheet metal casings having openings 60 and 5I in the bottom surfaces thereof through which projects rounded buttons 62-63 whose enlarged bases 64--65 are pressed by coil springs SI5-61. Plates 63;-69 are fitted inside the casings and the enlarged ends of the casings are crimped to retain the plates in place.

In the modified form of the tension device disclosed in Figs. 8 and 9 of the drawings, the

collecting, the yarn or thread receives adouble twist since the yarn package is stationary while the spindle through which the yarn is led rotates at a high rate of speed. The tensioning device inserted in the path of thread between the point of unwinding and the ballooning area, because of its adjustability, makes it possible to apply uniform tension on the thread and thus regulate the rate of take-oil' of thread from the yarn package.

The use of a tensioning device having outwardly pivoted arms as described permits the twister to be readily threaded and rethreaded if breakage occurs, and ready access for removing slubs, broken threads and the like. stated, however', the principal advantage of the presentinvention is the resultant uniform tension placed on the yarn.

' Experiments made with various materials for use in the braking or friction pads '50 and 5I have shown that a combination of spongerubber pads faced with a thin woven glass fabric has given very satisfactory results. In this combination, although the resiliency of the material is not impaired, the pads maintain a uniform flat surface and contact against the yarn passing therebetween. Byy having one pad adjustable -with relation to the other, as previously described, the tension between the abutting surfaces may be regulated with facility and a constant pressure between the pads continuously maintained. The adoption of glass fabric and rubber pads eliminates the scoring and indenting of the material by the thread as is usually experienced with ordinary resilient material, and the use of these novel brake surfaces in conjunction with adjustable spring pressure means has proven most satisfactory. If desired the brackets may also be equipped with a washboard tension device similar to those used on coning machines, in place of the aforementioned resilient pads.

It is to be understood that the form of our invention, herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape, size and ararrangement of parts may be resorted to without departing from the spirit of our invention or the scope of the subjoined claims. f

Having thus described our invention as re quired by the patent statutes, what we claim is:

/ l. A yarn twisting mechanism of the character As before c described comprising a rotating drive spindle, a non-rotating bobbin removably mounted on the free end of said spindle, and having a yarn package wound thereon, said spindle and bobbin having a. central yarn passage therethrough, and a tension device carried on the upper end of said bobbin, said device having a pair of pivoted arms having opposed and abutting friction surfaces thereon between which the yarn from said package is drawn to create a uniform tension therein.

2. A yarn twisting mechanism as set forth in claim 1, wherein the opposed friction surfaces are formed of pads consisting of non-scoring resilient material.

3. A yarn twisting mechanism as set forth in claim 1, wherein the opposed friction surfaces are formed o f resilient pads having glass cloth faces.

4. A yarn twisting mechanism as set forth in claim 1, wherein the tension device comprises a pair of upstanding pivoted arms between which the yarn from said package is drawn by the rotating spindleI and latch means carried on the upper ends ofthe arms for normally holding said arms in contact with each other.

5. A yarn twisting mechanism as set forth in claim 1, wherein the friction surfaces between which yarn is drawn are mounted on the opposing abutting faces of a pair of pivoted arms, with positive means for separating said arms.

6. A yarn twisting mechanism as set forth in claim 1, wherein the friction surfaces between which the yarn is drawn are mounted on pivoted arms, and resilient means amxed to one of said .arms for varying the degree of contact of one of the surfaces with the other of said surfaces.

7. A yarn twisting mechanism of the character described comprising a rotating drive spindle and a non-rotating yarn package mounted on the free end of said spindle, said spindle and yarn package having a central yarn passage therethrough, a hollow conical member removably mounted on the free end of said yarn package, said conical member having a pair of pivoted contacting arms secured therein between which the yarn from said package is drawn to create a uniform tension therein'.

8. A twisting apparatus of the type described including a xed hollow yarn package and a hollow rotating spindle mounted within the yarn package, a braking device interposed between the said yarn package and the said rotating spindle, said braking device being mounted on the upper end of said yarn package and comprising a centrally apertured hollow cone member, a pair of pivoted upstanding arms having abuttingatfriction faces secured within said cone, the central -aperture in said cone together with the inner surfaces of said friction facesbeing in vertical alignment with said rotating spindle.-

9. A twisting apparatus of the type described including a hollow rotating drive spindle and a non-rotating yarn bobbin removably mounted over an upstanding tube member surrounding said spindle, a removable yarn tensioning device supported on the free end of said bobbin and said tube member, said device comprising a substantially hollow cone member, a pair of opposed abutting arms pivoted therein, the upper ends thereof being latched within said cone, a yarn aperture in the apex of said cone above the said pivoted arms, opposite cutaway portionsin the surface of said cone, a horizontal bore in the surface of said cone midway between said cutaway portions, and a key adapted to be inserted in said bore and wedged between the lower portions of said arms, said Vkey upon rotation unlatching said arms and permitting them to pivot outwardly intothe said cutaway portions.

10. A twisting apparatus of the type `described including a. hollow -rotating spindle, 'a stationary tube surrounding said spindle, a yarn package re'- movably mounted over said spindle and tube, a removable yarn tension imparting'device mounted on the upper ends of said yarn package and said tube, said device comprising a hollow'cone having an oscillatable apex portion, a pair of pivoted arms secured within said cone, abutting braking faces carried on the said arms, each arm having an upwardly extendingspring projected latch vmember secured within the upperend thereof, cutaway portionsin said cone adjacent the rear of each of saidarms, and a pair of interrupted arcuate grooves formed on the underside of the oscillatable apex portion of said cone for normally retaining the said latch members and for releasing the same when the said apex portion is rotated through a one-quarter turn.

11. A twisting apparatus of the type described including a hollow rotating spindle, a stationary tube surrounding said spindle and a non-rotating yarn' bobbin removably mounted over said spindle and tube, a removable yarn tensioning device fltedover the end of said bobbin and said tube, a pair of pivoted arms carrying abutting glass cloth surfaces secured within said tension device, means for adjusting the degree of contact between said glass cloth surfaces and for separating the said surfaces, the yarn to be twisted being fed form tension in said yarn.

RALPH H. CARTER. RICHARD GOLLONG. CHADWICK B. KINGSBURY. 

